The psychological impact of looking good is so important that the national team cannot afford to ignore it. And the hot fashion tip at these games? Designer sunglasses.
"What the other teams are wearing is probably the major area of discussion in the Olympic village," said John Anderson, the Gladiators referee who, over the last 30 years, has coached more Olympic athletes than anyone else in Britain. "Looking good is crucially important, and if you're well dressed, you already feel better than the other teams. It's about one- upmanship."
It has taken Britain a long time to catch up with what's chic on the track. For years the French, Germans and Americans put Britain to shame. But for this Olympics, every British team manager for every sport has given personal approval for every piece of kit. Setting the fashion standard will be the sprinters, long recognised as the showmen of the track.
Psychological profiles suggest extrovert personalities are attracted to dynamic powerful events like sprinting. Linford Christie, for instance, has long had a taste for outlandish gear. At Atlanta, according to Lisa Broomhead, Olympic Project Manager for the British team, all the British men will be in Christie-style, figure-hugging all-in-ones. "It gives them confidence to wear something so outrageous, I suppose."
Among the women, the race for fashion is between the long distance runners, who wear briefs and cropped tops, cut as small as they can get away with, and the sprinters who wear the so-called "unitards", which look more like underwear than running gear.
"The unitard is a style thing," said John Anderson. "I don't think it has been proved to be more effective in performance, but some people feel more comfortable. If they are not happy and comfortable, it will have an adverse effect on performance."
The kit uses the latest in fabric technology: Coolmax with Lycra and Lycra Power, designed for Adidas by Du Pont. Both are intended to create a "microclimate" for the body, and help remove sweat.
"The biggest advantage we saw in Lycra Power is that it makes you look good," said Martina Fruhwald of Adidas International in Germany. "It makes your thigh muscles come together and you look a bit slimmer. The men didn't understand why we were so excited, but we thought it was great." It will be in Adidas's spring/summer collection next year.
It is sports sunglasses, however, that look like being the most influential development. Ray-Ban is trying to do for athletes what it once did for aviators and has brought out its first premium-range sunglasses specifically for the Olympics.
It is part of a market which has grown 25 per cent a year since Ian Botham first wore shades in a Test match. US sprinter Michael Johnson and German high jumper Javier Sotomayor have all done their bit. At least six other manufacturers havetheir sights on the Olympics.
In the Seoul Olympics, the American male sprinters claimed to have overcome a problem their rivals didn't know they had: hair drag.
Body hair has been proved to have a negative effect on runners, albeit minute. The American solution was unitards with aerodynamic hoods. "It was a gimmick," said Anderson, "but it was one that worked. Other athletes loved them. These were America's top sprinters, the likes of Carl Lewis and so on, and they were winning all the events anyway. But everyone looked at them, and knew they had something we didn't. I'm convinced it gave them a psychological advantage."
The first opportunity to psych out the opposition will come with the opening ceremony, and the parade of national uniforms, on Friday. In the past, some notorious faux pas have been made. Australia has an unpredictable reputation - it is sometimes brilliant, sometimes awful, while Ireland and Wales - at Commonwealth Games - have been famously dull. For the British team, the baton this year has passed from Next, which dressed the troops in Barcelona, to Aquascutum. The women's outfit at least makes it above the knee.
In Spain, in the heat, long skirts and sailor collars didn't make the British women feel much like marching, let alone be ambassadors for their country. They could only look on with envy at the chic, mini-skirted Spanish. "I gave my uniform away as soon as I got home," said one former employee of the British Olympic Association. "They were not exactly popular with anyone." Aquascutum, however has had problems of its own, having measured the team when it was several pounds heavier, due to athletes' winter fat. With just days to go general manager Tim Dally was still desperately arranging for 40 pairs of 32-inch trousers to be taken in in time to be airfreighted to Atlanta to catch up with the blazers.